AP Study Group students on Friday tackled the geologic timeline, researching the causes and effects of past extinction events. Small student groups were assigned events, spent time researching them online in class, then presented their findings to the rest of the students so that everyone could create their own comprehensive timeline to study. One tantalizing finding that students learned about was the discovery in deep sea beds of unusual heavy metals and carbon strands that did not exist in nature anywhere else on the planet. How did they get there? Are they possibly evidence of previous, unknown civilizations? Cue the “Twilight Zone” music!